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# CP Stopping Distance. (a) If the coefficient of kinetic

ISBN: 9780321675460 31

## Solution for problem 33E Chapter 5

University Physics | 13th Edition

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Problem 33E

CP Stopping Distance.? (a) If the coefficient of kinetic friction between tires and dry pavement is 0.80, what is the shortest distance in which you can stop a car by locking the brakes when the car is traveling at 28.7 m/s (about 65 mi/h)? (b) On wet pavement the coefficient of kinetic friction may be only 0.25. How fast should you drive on wet pavement to be able to stop in the same distance as in part (a)? (?Note:? Locking the brakes is ?not? the safest way to stop.)

Step-by-Step Solution:

Solution 33E After locking the brake, the car will slide on the ground, and because of the kinetic friction there will be deceleration and using the deceleration we can find out the distance required to stop the car. In the second part, we know the distance and we can calculate the deceleration of the car from dynamic friction. Using this two we can calculate the maximum speed. Step 1 Let us consider the mass of the car is m, hence the force due to kinetic friction is F = mg kf From the problem we know that, = 0.80 We also know that g = 9.8 m/s 2 Hence the force due to kinetic friction is 2 F kf = m(0.80)(9.8 m/s ) Fkf m(0.80)(9.8 m/s ) 2 So the deceleration of the car is a = m = g = m = 7.84 m/s Step 2 Initial speed of the car is u = 28.7 m/s Since the car is coming to rest, the final speed of the car is v = 0 m/s 2 And the acceleration is a = 7.84 m/s Now from the dynamics we know that v = u 2as Putting values we have 0 = (28.7 m/s) 2(7.84 m/s )s s = (28.7 2/s= 1.83 m 2(7.84 m/s ) So the shortest distance to stop the car by locking the brake is 1.83 m. (b)

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##### ISBN: 9780321675460

University Physics was written by and is associated to the ISBN: 9780321675460. The full step-by-step solution to problem: 33E from chapter: 5 was answered by , our top Physics solution expert on 05/06/17, 06:07PM. The answer to “CP Stopping Distance.? (a) If the coefficient of kinetic friction between tires and dry pavement is 0.80, what is the shortest distance in which you can stop a car by locking the brakes when the car is traveling at 28.7 m/s (about 65 mi/h)? (b) On wet pavement the coefficient of kinetic friction may be only 0.25. How fast should you drive on wet pavement to be able to stop in the same distance as in part (a)? (?Note:? Locking the brakes is ?not? the safest way to stop.)” is broken down into a number of easy to follow steps, and 89 words. This full solution covers the following key subjects: stop, Pavement, distance, Wet, Car. This expansive textbook survival guide covers 26 chapters, and 2929 solutions. Since the solution to 33E from 5 chapter was answered, more than 277 students have viewed the full step-by-step answer. This textbook survival guide was created for the textbook: University Physics, edition: 13.

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CP Stopping Distance. (a) If the coefficient of kinetic

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